Thermoplastic lamp holder

ABSTRACT

A multiple lamp holder is disclosed which is characterized by its simplicity of construction. The lamp holder is made up of four pieces: two conductive terminals, an insulating bushing which holds the two terminals apart and an insulating housing which is molded in a single piece and consists of two complementary halves of the housing joined together in a hinged relationship so that the two halves may be folded together so as to enclose the terminals and bushing and the resulting structure need only to be sealed along a single seam.

United States Patent [72] Inventor Larry L. Shroyer Wolcottville, Ind.[21] Appl. No. 813,610 [22] Filed Apr. 4, 1969 [45] Patented May 25,1971 [73] Assignee Lyall Electric, Inc.

Albion, Ind.

[54] THERMOPLASTIC LAMP HOLDER 7 Claims, 5 Drawing Figs. [52] US. Cl339/160, 339/62 [51] Int. Cl H01r 13/48 [50] Field of Search 339/160,149,159,160,155 L, 199, 59, 60-63, 208, 210, 116; 174/92, 138.4

[56] References Cited UNITED STATES PATENTS 1,532,208 4/1925 Strongson339/160 2,502,860 4/1950 Leithiser, Jr 18/59 3,072,875 l/l963 Johnson etal. 339/218X FOREIGN PATENTS 863,386 3/1961 Great Britain 339/62 PrimaryExaminer-Richard E. Moore AttorneyJeffers and Rickert PATENTEU "H25 I971INVENTOR.

LAR'RY L. SHROYER THERMOPLASTIC LAMP HOLDER This invention relates tosockets for light bulbs and more specifically to a multiple bulb socketor multiple lamp holder.

Prior art lamp holders have the primary defect that they are relativelyexpensive to manufacture. They generally consist of a large number ofparts and the assembly process is relatively difficult and costly. Theprior art lamp holders have the further drawback that the shell contact,that is the portion that contacts the threaded portion of the light bulbhas a relatively complex configuration and is difficult to fabricate.These and other disadvantages of the prior art lamp holders are overcomeby the present invention which provides for a pair of relatively simplecontacts which may be fabricated from flat sheet material. A simplenonconductive bushing is used to hold the two contacts apart and thesethree parts are enclosed in a one-piece nonconductive housing. Thishousing is initially molded in one piece having two complementaryhalvesjoined along one edge in a hinged relationship. Thus one of thehalves may be rotated about this hinge with respect to the other halfthrough 180 to form the socket housing. The housing then appears toconsist of two halves joined along two seams, the first seam being thehinge portion. The second seam is then sealed, for example, by heatingto form a completed socket assembly.

Accordingly, it is one object of the present invention to provide aneconomical socket structure.

It is another object of the present invention to provide a multiple lampholder characterized by a minimum number of component parts.

It is a further object of the present invention to provide a method ofmanufacturing a multiple lamp holder which facilitates assembly of theholder.

It is another object of the present invention to provide an economicalmethod of manufacturing a lamp holder.

These and other objects and advantages of the present in vention will bemore readily seen from the following description given in connectionwith the accompanying drawing in 'which:

FIG. 1 is a perspective view of the assembled lamp holder;

FIG. 2 is a perspective view of the partially assembled lamp holder;

FIG. 3 is an end view of the lamp holder;

FIG. 4 is a cross-sectional view taken along the line 4-4 of FIG. 5; and

FIG. 5 is a cross-sectional view taken along the line 5-5 of FIG. 3.

Referring first to FIG. 1 the completed lamp holder or bulb socket isseen to consist of a pair of terminals I and 2 exterior of the housing 3which form a male plug. The socket has a threaded aperture 4 into whicha bulb or lamp is to be inserted. The specific structure of the socketis most easily seen in FIG. 2 which shows the interior portion of thehousing including two threaded apertures 4 and 5. The socket is seen tocontain two conductors, the first conductor comprising a single smooth,curved, resilient, conductive strip portion 7 and a prong portion I. Thesecond conductor is seen to comprise a prong portion 2 and a centralportion 8 which is adapted to simultaneously Contact a pair of baseterminals of a pair of bulbs which would be threaded into the twoapertures. FIG. 2 shows the two complementary halves of thenonconductive lamp housing being joined along the dotted line 6. The twohalves may be joined along the entire length of the straight line 6 ormay be joined along only portions thereof. In either event this line 6acts as a hinge so that one-half of the housing may be revolved aboutthe straight line 6 through 180 so as to close and give the appearanceof the completed socket of FIG. 1. When hinged shut inthis fashion,there is seen to result two seams 9 and 10 as illustrated in FIG. 3. Theseam I0 is seen to require no further attention since the hinge portion6 holds it shut. The seam 9 is heated or otherwise sealed so as to holdthe housing shut in its final form.

Returning now to FIG. 2 the first conductor is seen to have been formedfrom a T-shaped flat piece of conductive material by bending the base ofthe T through 90 and the second conductor is seen to have been formedfrom a different (taller and less wide) T-shaped flat piece ofconductive material by bending each of the symmetrically oppositelyextending portions of the T upwardly through Tlhus either of theseconductors may be fabricated by the relatively simple process ofstamping out a T-shapcd piece from flat stock material and performingone simple 90 bending operation in the case of the shell contact and twosimple 90 bending operations in the case of the base contact.Additionally, these conductors may be provided with holes which willallow them to pass over and be aligned by the pins 11 and 12 which areintegral parts of the lamp housing. A cylindrical insulating bushing 13as shown in FIG. 4 may optionally be provided to separate and hold thetwo conductors down on the pins 11 and 12.

Referring now to FIG. 5' the curved shape of the conductive strip 7 isreadily apparent. This curve provides a spring action when a bulb isscrewed into either of the apertures 4 or 5. Assume for the moment thata bulb has been screwed into aperture 4. It's center base terminal willbe in contact with the left side of the central portion 8 and its shellcontact will be touching the left part of the conductive strip 7. Thespring action of the conductive strip 7 will hold the shell or threadedportion of the bulb securely in the threaded portions of thenonconductive housing.

The two conductors may be fabricated from any suitable metallicconductor. The nonconductive housing may be made ofa thermoplasticmaterial which will allow the seam 9 of FIG. 3 to be easily sealed byheating the seam. A thermosetting plastic material such as nylon hasbeen found suitable for one embodiment of this invention. Thecylindrical insulating bushing may be made from a similar material andin one embodiment of the present invention teflon was used for thisbushing. The threaded portion of the housing could be constructed so asto accept a bayonet base bulb.

In lieu of the cylindrical bushing illustrated as a separator for thetwo conductors, a potting material such as epoxy could be caused to flowbetween the conductors to provide a moisture proofseal.

The lamp holder mounting configuration illustrated could be modified toconform with any mounting surface or aperture therein.

The prong portions of the conductors could be terminated within thehousing, leads affixed thereto, and the leads then caused to protrudeexterior of the housing. Therefore, while the invention has beendescribed with reference to a particular embodiment it is to beunderstood that modifications may be made without departing from thespirit of the invention or from the scope of the appended claims.

I claim:

I. A multiple bulb socket comprising;

a nonconductive housing formed with two threaded apertures and having aninterior and an exterior portion;

a pair of terminals exterior of said housing forming a plug;

a first T-shaped conductor which has been deformed in a first waycomprising a single smooth curved resilient conductive strip portioninterior of said housing adapted to connect together a pair of shellcontacts of a pair of bulbs and a prong portion extending to theexterior of said housing to form one of the pair of terminals;

a second T-shaped conductor which. has been deformed in a second waycomprising a prong portion extending exterior of said housing formingthe second of said pair of terminals and a central portion interior ofsaid housing adapted to simultaneously contact a pair of base terminalsof a pair of bulbs; and

an insulating bushing having ends which engage and separate said firstand second conductors.

2. The socket of claim 1 wherein said nonconductive housing comprises asingle molded piece of thermoplastic material.

3. The socket of claim I wherein said insulating bushing is a hollowcylindrical bushing further comprising a pair of alignment pins, eachsaid pin extending through one conductor and into one end of said hollowbushing.

4. A method of manufacturing a multiple lamp holder comprising:

molding, in a single piece, the two complementary halves of thenonconductive lamp housing;

forming and inserting a first and a second conductor, said step offorming and inserting comprising; forming the first conductor from aT-shaped flat piece of conductive material by bending the base of the Tupwardly through substantially a right angle, forming the secondconductor from a different T-shaped flat piece of conductive material bybending each of the symmetrically oppositely extending portions of the'l' upwardly through substantially a right angle, and inserting each ofthe so-deformed conductors into the lamp housing;

providing a basing with ends engaging and separating said first andsecond conductors;

folding said complementary halves together; and scaling the resultingseam.

5. The method of claim 4 wherein the step of sealing comprises:

heating the vicinity of the seam so as to fuse the material in thevicinity of the seam.

6. A method of manufacturing a multiple lamp holder comprising: i

molding, in a hinged relationship, the two complementary halves of thenonconductive lamp housing; forming and inserting a first and a secondconductor, said step of forming and inserting comprising; forming thefirst conductor from a T-shaped flat piece of conductive material bybending the base of the T upwardly through substantially forming thesecond conductor from a different T-shaped flat piece of conductivematerial by bending each of the left and right portions of the Tupwardly through substantially 90, inserting each of the soformedconductors into the lamp housing, and providing a bushing with endsengaging and separating said first and second conductors; folding saidcomplementary halves together; and sealing the resulting seam. 7. Themethod of claim 6 wherein the step of sealing comprises heating thevicinity of the seam so as to fuse the material in the vicinity of theseam.

1. A multiple bulb socket comprising; a nonconductive housing formedwith two threaded apertures and having an interior and an exteriorportion; a pair of terminals exterior of said housing forming a plug; afirst T-shaped conductor which has been deformed in a first waycomprising a single smooth curved resilient conductive strip portioninterior of said housing adapted to connect together a pair of shellcontacts of a pair of bulbs and a prong portion extending to theexterior of said housing to form one of the pair of terminals; a secondT-shaped conductor which has been deformed in a second way comprising aprong portion extending exterior of said housing forming the second ofsaid pair of terminals and a central portion interior of said housingadapted to simultaneously contact a pair of base terminals of a pair ofbulbs; and an insulating bushing having ends which engage and separatesaid first and second conductors.
 2. The socket of claim 1 wherein saidnonconductive housing comprises a single molded piece of thermoplasticmaterial.
 3. The socket of claim 1 wherein said insulating bushing is ahollow cylindrical bushing further comprising a pair of alignment pins,each said pin extending through one conductor and into one end of saidhollow bushing.
 4. A method of manufacturing a multiple lamp holdercomprising: molding, in a single piece, the two complementary halves ofthe nonconductive lamp housing; forming and inserting a first and asecond conductor, said step of forming and inserting comprising; formingthe first conductor from a T-shaped flat piece of conductive material bybending the base of the T upwardly through substantially a right angle,forming the second conductor from a different T-shaped flat piece ofconductive material by bending each of the symmetrically oppositelyextending portions of the T upwardly through substantially a rightangle, and inserting each of the so-deformed conductors into the lamphousing; providing a basing with ends engaging and separating said firstand second conductors; folding said complementary halves together; andsealing the resulting seam.
 5. The method of claim 4 wherein the step ofsealing comprises: heating the vicinity of the seam so as to fuse thematerial in the vicinity of the seam.
 6. A method of manufacturing amultiple lamp holder comprising: molding, in a hinged relationship, thetwo complementary halves of the nonconductive lamp housing; forming andinserting a first and a second conductor, said step of forming andinserting comprising; forming the first conductor from a T-shaped flatpiece of conductive material by bending the base of the T upwardlythrough substantially 90*, forming the second conductor from a differentT-shaped flat piece of conductive material by bending each of the leftand right portions of the T upwardly through substantially 90*,inserting each of the so-formed conductors into the lamp housing, andproviding a bushing with ends engaging and separating said first andsecond conductors; folding said complementary halves together; andsealing the resulting seam.
 7. The method of claim 6 wherein the step ofsealing comprises heating the vicinity of the seam so as to fuse thematerial in the vicinity of the seam.